Kinekard

Curtain and Nayler¹ isolated, in 1963, from human blood plasma a substance with a positive inotropic or muscle-stimulating action on the toad heart. The substance was isolated by ion exchange chromatography and was proved to be a previously unknown plasma factor. In 1965, Lowe and Nayler² proposed naming this new substance "kinekard," a term indicating its influence upon cardiac kinetics. In 1967, Dorevitch et al³ discovered that kinekard acted as a constrictor on the rabbit thoracic aorta; however, strips of rabbit ileum and guinea pig uterus were relaxed by the action of the agent. They also proved that kinekard and epinephrine were not one and the same substance. In May 1969, Lowe⁴ presented a detailed description of kinekard's physiological action. He confirmed the relaxant action of the agent on coronary vessels and also presented evidence that its inotropic and pressor activities were independent of each other.